The role of the Center for Small Animal Imaging in the Vanderbilt University Institute of imaging Science in this P50 will be to develop and apply multi-modality imaging technologies for the comprehensive evaluation and characterization of the evolving minor microenvironment in the biological systems used to validate and provide input data for the mathematical models ef cancer. It will tbcus on combining the information from different modalities, including high field (9.4T) magnetic resonance imaging (MRI), bioluminescence, microCT, microPET, and ultrasound, to measure critical morphological, and biophysical features of in vitro and in vivo models of cancer to provide input for the mathematical models, and data with which to test model performance.